A device of this type has become known from DE 43 04 891 C2. A half mask, which is pressed against the mouth and nose by means of a strap extending at the back of the head, is located within a protective hood, which consists of a supple material. A breathing filter, via which the user of the hood is supplied with breathing air, is located at the half mask. The strap comprises individual, elastic straps, which are sewn together and are connected in a punctiform manner to the inside of the hood. The hood is dimensioned such that it accurately fits the heads of persons of different ages and has a window, which consists of a heat-resistant and chemical-resistant material. In case of danger, for example, in a fire, the hood must be pulled over the user's head and the half mask must now be sealingly in contact with the mask user's face. The drawback of the prior-art device is that by fastening the half mask at two opposite points, pressure points may develop on the mask user's face and when the hood is pulled over, the half mask will not be sealingly in contact with the mask user's face.